Stairway.



PATENTED AUG. 30, 1904.

LKULHNEK.

STAIRWAY.

APPLICATION FILED 00127, 190s.

No MODEL.

MZWSSES y@ y m/ Patented August 30, 1904,

PATENT Ormea.

JAN KULHNEK, ()F\PRAGUE, AUSTRIA-HUNGARY.

STAIRWAY.

SPECIFICATION forming part of Letters Patent Non 768,759, dated August 30, 1904.

Application filed October 7, 1903. Serial No. 176,163. (No model.)

To all wil/071i, it may concern:

Be it known that I, JAN KULHNEK, a subject of the Emperor of Austria-Hungary, residing' at Prague, Austria-Hungary, have invented certain new and useful Improvements in Stairways; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which itappertains to make and use the same.

The present invention relates to improvements in stairways made of cement, artificial stone, or similar material which are arranged in longitudinal and transverse ribs crossing each other, said ribs being reinforced by metal bars or wire, of which the longitudinal bars extending' from one landing to another are especially adapted to take up the strain.

In the accompanying drawings, forming part of this specification, Figure l shows a longitudinal section through a stair-arm in the process of construction with the scaffolding under the same. Fig. 2 is a longitudinal section through a stair-arm ready made, the scaffolding being removed. Fig. 3 is across-section on line A B of' Fig. 2, and Fig.. 4 is a similar cross-section through a slightly-modified form.

In building up stairways according to my invention a board scaffolding n is erected hetween two landings liaving the inclination of the stair-arm to be established thereon. A netting of wire or metal rods is placed upon the scaffolding composed of longitudinal rods or wires c and of transverse rods or wires L. The distance between the rods is equal tothe distances in which the longitudinal and transverse ribs of cement should be formed. rIhe transverse bars are preferably placed at such a distance that they are exactly in line with the risers to be formed. In the squares formed by the crossing bars b c mold-blocks are set, which ca n be solid, as indicated by the letter p, or hollow, as shown by the letter t in Fig. l. The said blocks are set in such a manner that spaces between them of five to ten centimeters in widthare left open and that they run regularly longitudinally as well as transversely in rows, whereupon the spaces between them are filled with cement, mortar, or material Vto form artificial stone, which is poured into the'said spaces, so that vertical ribs r and g are formed. The ribs r run longitudinally and the ribs q transversely, all being in line above one of the iron rods and forming together a solid grating. Vhen the material is sufficiently hard, the visible surfaces of the blocks on top and front side are covered with the mass of cement or mortar to form the step-plates c and the risersw, and moldings may be drawn at the edges in the ordinary well-known manner. The stair-arm is then ready, and after allowing the cement to set the scaffolding beneath can be removed and the mold-blocks can be withdrawn from below. After two or three days drying the stair-arm can be used with safety. The spaces which have been occupied by the mold-blocks can remain open or can be closed by woodwork or a sheet of mortar. In this latter case it is only necessary to begin the construction of the stair-arm with asheet of mortar cement a, which is spread upon the board surface of the scaffolding, (not shown in Fig. 4,) whereupon the wire-netting c is brought in place as above described. The mold-blocks 15in this instance are preferably hollow and are made of light and thin material, such as wood, pasteboard, and the like. The grate of cement and the risers and step-plates are-now produced in the same way as above described.

I claim- 1. Stairways of cement, artificial stone, mortar, grout, or similar material composed of' vertical transverse ribs forming downward projections of the risers and being in the same plane therewith and of vertical longitudinal ribs, running parallel in the stair-arm from landing to landing, transversing the cross-ribs and forming a grating therewith, said longitudinaland transverse ribs being reinforced by metal rods, bars or strips, forming a netting which corresponds to said grating, the risers and steps of the stairs being formed above said grating of the same material as and integral with the grating, substantially as described.

2. Stairways of cement, artificial stone,

`mortar, grout or similar material composed of vertical transverse .ribs forming downward IOO projections or' the risers and being in the l formed above said grating of the Same inan IO saine plane therewith and ofvertical longitui terial as and integral with the grating' and (linal ribs1 running parallel in the stair-arm l of a Sheet, closing up the lower surface of the Vfrom landing to landing, transversing the stairway substantially as described.

5 cross-ribs and forming va grating therewith ln testimony whereof l affix my Signature. said longitudinal and transverse ribs being JAN KULHNEK, reinforced by metal rods, bars or strips, form- In presence of ingl a netting which corresponds to Said grat- KAREL BOUBLIK7 ing, the risers and Steps of the stairs being ARTHUR SCHWEZ, 

